A40-43 Invasive Aspergillosis in a Case of Pulmonary Alveolar Microlithiasis

Abstract Pulmonary alveolar microlithiasis (PAM) is a rare, chronically progressive lung disease characterized by the accumulation of calcium phosphate crystals within the alveoli. In most patients, PAM is discovered incidentally during radiological examinations performed for other reasons. The typical course of the disease involves slowly progressive respiratory failure over several decades. The majority of reported cases in the literature come from Turkiye, where the disease is known to follow an autosomal recessive pattern of inheritance. Our patient was a 72-year-old man who had been previously diagnosed with PAM, confirmed radiologically and pathologically. He presented to the emergency department with gradually worsening shortness of breath, exertional dyspnea, and cough. On physical examination, digital clubbing was noted. On auscultation, coarse breath sounds were heard in both upper zones, and fine crackles were present in the mid and lower lung zones. Chest X-ray revealed diffuse, sand-like micronodular opacities, more prominent in the basal regions compared to the apices. On thoracic CT, parenchymal window images showed widespread millimetric calcified nodules, more pronounced in the lower lobes, accompanied by a cavitary lesion in the left upper lobe. The patient was evaluated in the emergency department with a preliminary diagnosis of pneumonia and was consulted to the Department of Pulmonology. We performed fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) sampling from the cavitary lesion in the left upper lobe. The BAL specimen was sent for aerobic bacterial, fungal, and tuberculosis cultures, as well as TB smear, PCR, and galactomannan antigen testing to investigate possible fungal infection. The galactomannan antigen test was positive for Aspergillus species, and Aspergillus fumigatus was later isolated from the BAL fungal culture. Based on these results, the patient was diagnosed with invasive pulmonary aspergillosis (IPA). Voriconazole therapy was started, and clinical improvement was observed during follow-up. The patient was discharged on oral voriconazole and continues to be followed up in the outpatient clinic. Invasive pulmonary aspergillosis is a severe fungal infection with a high mortality rate. Its incidence has been increasing due to the growing number of patients undergoing bone marrow transplantation, chemotherapy, and immunosuppressive therapy. Furthermore, airway and parenchymal damage may facilitate colonization and invasion of Aspergillus spores. In rare diseases such as PAM, where chronic parenchymal fibrosis, repeated emergency admissions, and frequent steroid use are common, IPA should also be considered in the differential diagnosis of cavitary pneumonias. This case aims to emphasize that possibility. This abstract is funded by: none